A viscometer for mineral suspensions

The measurement of the viscosity of mineral slurries, using a modified falling-ball viscometer, is described. In the system used, a plummet was pulled vertically through the slurry under test at a rate governed by an external weight. The velocity of the plummet was established by means of two Geiger tubes outside the viscometer tube, which were actuated by a small radioactive source inside the 'plummet. The viscosity of suspensions of glass balls, barite and galena was compared at different rates of shear, and the variation in flow characteristics, in particular the non- Newtonian nature of the viscosity of the mineral slurries, was clearly demonstrated. The use .and limitations of a viscometer of this kind, for measuring the viscosity of slurries, are discussed.